NaA , CaA 및 Alumina 상에서 Dichlorodifluoromethane 중의 수분의 흡착분리 특성

하백현,박건용,이영섭 한국화학공학회 1986 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.24 No.4

Dichlorodifluoromethane中에 含有되어 있는 微量의 水分을 選擇 吸着하는데 效果的인 吸着劑를 검토하기 위해 제올라이트 A와 活性알루미나상에서 물의 吸着 및 脫着特性과 破過曲線을 測定·硏究하였다. 가스크로마토그라프에 의해 低壓領域에서 吸着等溫線과 昇溫 熱脫着曲線을 구하였으며 이로부터 구한破過曲線으로부터 分子瀘過作用을 하는 제올라이트 A가 活性알루미나보다 dichlorodifluoromethane중에 함유된 水分의 分離效果가 좋음을 알았다. CaA가 NaA보다 吸着容量은 컸으며 脫着에서는 NaA가 더 容易한 것을 확인하였다. The adsorption and desorption properties of water and breakthrough curves of dichlorodifluoromethane-water system were measured on zeolite NaA, CaA, and activated alumina to see the adsorption characteristics, which are effective for the separation of water from dichlorodifluoromethane-water mixture gas. The adsorption isotherms at low equilibrium pressure and the temperature programmed desorption curves of water were measured by gas chromatography. The separation of water from dichloroditluoromethane on molecular sieving zeolite A has been found to be more effective than on activated alumina by comparing breakthrough curves which were determined from the measured isotherms. It may be ascertained that NaA is the most effective adsorbent from a standpoint of the regeneration by desorption process, although CaA adsorbs water more than NaA.

화학제품 제조업에서 발생한 VOC의 탈착반응 연구

박근익 ( Kun Yik Park ),윤성민 ( Sung Min Yoon ),김주연 ( Joo Yeon Kim ),길인섭 ( In Sub Kil ),박희재 ( Hi Jae Park ),이영우 ( Young Woo Rhee ) 한국공업화학회 2010 공업화학 Vol.21 No.5

시화/반월 산단 내에서 활성탄 흡착탑을 사용하는 업종 중 기타 화학제품 제조업종에서 수거한 폐활성탄의 탈착반응특성을 조사하였다. 탈착특성을 조사하기 위하여 열중량분석기(Thermogravimetric Analyzer, TGA)가 사용되었다. 탈착반응특성 비교에 중요한 요소인 반응차수와 활성화 에너지를 구하기 위하여 Friedman법과 Freeman-carroll법을 사용하였다. 기타 화학제품 제조업종에서 수거한 폐활성탄으로 Friedman법을 이용하여 활성화 에너지를 계산한 결과, 24.8∼46.5 kJ/moL을 나타내었으며, Freeman-carroll법을 이용하여 반응차수와 활성화 에너지를 계산한 결과, 반응차수는 0.11∼1.69, 활성화 에너지는 8.77∼32.26 kJ/moL이었다. The characteristics of desorption reaction for spent activated carbon produced from the manufacture of other chemical products in Shiwha/Banwal industrial complex were investigated. TGA (Thermogravimetric Analyzer) was used to study for characteristics of desorption and kinetics. Then Friedman method and Freeman-carroll method were used to find the activation energy and the order of reaction. Activation energy by Friedman method was 24.82∼46.49 kJ/moL. And then activation energy and order of reaction by Freeman-carroll method were 8.77∼32.26 kJ/moL and 0.11~1.69.

β-Glucosidase 생산 유산균주의 분리와 이를 이용한 팽화홍삼 추출액의 생물전환

심건섭 ( Kun Sub Shim ),박귀근 ( Gwi Gun Park ),박영서 ( Young Seo Park ) 한국산업식품공학회 2014 산업 식품공학 Vol.18 No.4

팽화홍삼에 존재하는 major ginsenoside를 minor ginsenoside로 생물전환하기 위하여 β-glucosidase 활성이 높은 유산균주를 탐색하였다. 된장으로부터 분리한 YLB 8 균주가 β-glucosidase 활성이 가장 높았으며 Leuconostoc mesenteroides로 동정되었다. L. mesenteroides YLB 8을 MRS 배지에서 배양하였을 경우 최대의 β-glucosidase 효소 활성을 나타내기 위한 최적 배양 조건은 glucose 첨가량 1%(w/v), 초기 pH 8.0, 배양온도 30oC, 배양시간 16시간이었다. L. mesenteroides YLB 8을 이용하여 팽화홍삼 추출액을 생물전환하였을 경우 최적 온도는 30oC었으며, 팽화홍삼 추출액의 농도는 12oBx이었다. 팽화홍삼 추출액내에 존재하는 major ginsenoside인 Rb1과 Rb2는 minor ginsenoside인 Rg3로 전환되었으며, Re는 Rg1으로 전환되었으며, 이 중 일부는 Rh1과 Rh2로 전환되었다. Lactic acid bacteria producing high levels of β-glucosidase were screened to convert the major ginsenosides into the minor ginsenosides in puffed red ginseng. A strain named YLB 8 isolated from doenjang showed the highest β- glucosidase activity and was identified as Leuconostoc mesenteroides. The optimum conditions for the maximum production of β-glucosidase, when L. mesenteroides YLB 8 was cultured in MRS medium, were as follows; glucose concentration of 1% (w/v), initial pH 8.0, culture temperature of 30oC, culture time of 16 h. When Puffed red ginseng extract was bioconverted using L. mesenteroides YLB 8, the optimum temperature and the concentration of Puffed red ginseng extract was 30oC and 12oBx, respectively. As a result of bioconversion, the major ginsenosides Rb1 and Rb2 were converted into minor ginsenoside Rg3, and Re was converted into Rg3 and successively into Rh1 and Rh2 in part.

Multifunctional Tumor pH-Sensitive Self-Assembled Nanoparticles for Bimodal Imaging and Treatment of Resistant Heterogeneous Tumors

Ling, Daishun,Park, Wooram,Park, Sin-jung,Lu, Yang,Kim, Kyoung Sub,Hackett, Michael J.,Kim, Byung Hyo,Yim, Hyeona,Jeon, Yong Sun,Na, Kun,Hyeon, Taeghwan American Chemical Society 2014 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.136 No.15

<P>Nanoparticle-based diagnosis–therapy integrative systems represent an emerging approach to cancer treatment. However, the diagnostic sensitivity, treatment efficacy, and bioavailability of nanoparticles as well as the heterogeneity and drug resistance of tumors pose tremendous challenges for clinical implementation. We herein report on the fabrication of tumor pH-sensitive magnetic nanogrenades (termed PMNs) composed of self-assembled iron oxide nanoparticles and pH-responsive ligands. These PMNs can readily target tumors via surface-charge switching triggered by the acidic tumor microenvironment, and are further disassembled into a highly active state in acidic subcellular compartments that “turns on” MR contrast, fluorescence and photodynamic therapeutic activity. We successfully visualized small tumors implanted in mice via unique pH-responsive <I>T</I><SUB>1</SUB>MR contrast and fluorescence, demonstrating early stage diagnosis of tumors without using any targeting agents. Furthermore, pH-triggered generation of singlet oxygen enabled pH-dependent photodynamic therapy to selectively kill cancer cells. In particular, we demonstrated the superior therapeutic efficacy of PMNs in highly heterogeneous drug-resistant tumors, showing a great potential for clinical applications.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2014/jacsat.2014.136.issue-15/ja4108287/production/images/medium/ja-2013-108287_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja4108287'>ACS Electronic Supporting Info</A></P>

Design and Characterization of N-MCT with Low V<SUB>th</SUB> Off-FET for High Current-drive Capability

Sung-Kyu Kwon,Doo-Hyung Cho,Jong-Il Won,Hyun-Gyu Jang,Dong-Yun Jung,Joo-Sung Lee,Chang-Sub Kwak,Kun-Sik Park 대한전자공학회 2020 Journal of semiconductor technology and science Vol.20 No.6

In this paper, an N-MCT with a low threshold voltage of off-FET has been investigated by simulation and experiment. We have demonstrated the MCT with self-aligned spacer formation and recess process, which results in uniform off-FET channel length. And boron is implanted to adjust the threshold voltage of off-FETs. The threshold voltage of non-doped and proposed MCT was -1.2 V and 0.6 V, respectively. The forward blocking voltage of both MCTs was similar to 1800 V and the turn-on voltage of MCTs was 0.2 V and 0.75 V, respectively. The non-doped and proposed MCTs exhibit the same di/dt around 35.7 kA/㎲ and peak current of 2.69 kA. That is pointed out that this proposed MCT structure is promising because the current driving capability is improved without degradation of on-state characteristics.

실관막관에서 Lix84 에 의한 중금속 추출

박동원,이성식,최대웅,신군섭 한국공업화학회 1998 응용화학 Vol.2 No.1

Extraction by hollow fibers are fast compared with conventional extractional equipment because of the large surface area per volume, and the feeds can be contacted at high speed and two flows are completely independent, so there no problems withlaoding, flooding and channeling. In this paper, it was investigated the flow rate of aqueous and organic solution by using the hollow fiber membrane. It is known that the mass transfer is done as the flow rate of aqueous phase increase. For the system with high distribution ratio, effect of the distribution ratio on mass transfer was weak in system in the hollow fiber membrane.

Optoelectronic and microwave transmission characteristics of indium solder bumps for low-temperature flip-chip applications

Kun-Mo Chu,Jung-Hwan Choi,Jung-Sub Lee,Han Seo Cho,Seong-Ook Park,Hyo-Hoon Park,Duk Young Jeon Institute of Electrical and Electronics Engineers 2006 IEEE transactions on advanced packaging Vol.29 No.3

<P>This paper describes low-temperature flip-chip bonding for both optical interconnect and microwave applications. Vertical-cavity surface-emitting laser (VCSEL) arrays were flip-chip bonded onto a fused silica substrate to investigate the optoelectronic characteristics. To achieve low-temperature flip-chip bonding, indium solder bumps were used, which had a low melting temperature of 156.7degC. The current-voltage (I-V) and light-current (L-I) characteristics of the flip-chip bonded VCSEL arrays were improved by Ag coating on the indium bump. The I-V and L-I curves indicate that optical and electrical performances of Ag-coated indium bumps are superior to those of uncoated indium solder bumps. The microwave characteristics of the solder bumps were investigated by using a flip-chip-bonded coplanar waveguide (CPW) structure and by measuring the scattering parameter with an on-wafer probe station for the frequency range up to 40 GHz. The indium solder bumps, either with or without the Ag coating, provided good microwave characteristics and retained the original characteristic of the CPW signal lines without degradation of the insertion and return losses by the solder bumps</P>

만성변비환자에서 대장통과 시간 측정의 유용성

이건영,심강섭,김광호,박응범 대한대장항문학회 1998 Annals of Coloproctolgy Vol.14 No.3

NaY 상에서 몇가지 방향족 탄화수소의 흡착특성

박건유,하백현,이영섭 한국화학공학회 1985 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.23 No.2

Sodium Y zeolite 와 benzene, toluene, ethylbenzene, xylenes과 같은 芳香族 炭化水素가 이루는 吸着系에 대한 吸着特性을 溫度範圍 140∼280℃에서 Gas chromatography를 使用하여 硏究하였다. 또한 cyclohexane, n-pentane 그리고 n-pentene에 대해서도 調査, 比較하였다. Benzene 誘導體에 대한 吸着은 吸着量에 따른 吸着熱이 增加하는 것으로 보아 NaY에서 均一한 吸着系를 갖고 있는 것으로 判斷되며 吸着量과 吸着熱은 알킬기의 置換程度에 따라 增加하였고 이온화 포텐셜이 增加할수록 初期吸着熱은 減少함을 보였다. 이 吸着系에 細孔의 充塡槪念을 導入한 Dubinin-Astarkhov式을 適用시켜 본 結果 n-pentane과 cyclohexane系가 比較的 잘 適用되었으며 n-pentene과 benzene 誘導體는 상당한 偏差를 보여주었다. 또 Sodium Y와 같이 細孔이 큰 構造를 갖고 있는 zeolite에서는 吸着分子크기의 영향보다는 π電子와 알킬기의 영향이 더 큼을 確認하였다. The adsorptive characteristics of sodium Y zeolite for simple aromatic hydrocarbons, such as benzene, toluene, ethylbenzene, xylenes were investigated by means of gas chromatography at 140 to 280℃. For comparison, the adsorptive characteristics made from the isotherm curves, previously published, for cyclohexane, n-pentane and n-pentene on NaY zeolite were also checked. Sodium Y zeolite seems to form a homogeneous system for aromatic compounds. The amount adsorbed and the adsorption heat for benzene derivatives increase with the extent of alkyl substitution. A linear relationship was confirmed between the decrease in the ionization potential of aromatic hydrocarbons and the increase in the initial heat of adsorption. The Dubinin-Astarkhov's equation based on the Polanyi's theory was also applied on the adsorption system. The Dubinin-Astarkhov's equation was fitted well for cyclohexane and n-pentane but not for benzene derivatives and n-pentene. It was found that the adsorption with regard to the large pore zeolite such as sodium Y was preferably affected by the electrons and the extent of alkyl substitution rather than the kinetic diameter of adsorbate.

방사선 선형가속기를 이용한 심부뇌병소의 뇌정위적 수술

박성찬,김문찬,박춘근,강준기,송진언,오윤경,윤세철,최규호,신경섭,박용휘 대한신경외과학회 1989 Journal of Korean neurosurgical society Vol.18 No.1

It was already reported in else where that a standard linear accelerator, with only slight modification can function in a manner similar to Leksell's Gamma unit device in the treatment of inoperable deep seated intracranial lesions. Using collimated narrow beams, a localization system and special computer programs for precise patient positioning and a high concentration of irradiation dose within the lesions, eleven patients with AVMs and brain tumor have now been treated since 1988. The 6 MeV linear accelerator and Hitchcock stereotactic frame was used for the all procedures. In 10 of the 11 patients no side effects occurred. The first 7 patients, who could be observed 3 months or longer have been studied radiologically and clinically. In 6 patients marked decrease in contrast enhancement and marked, sometimes dramatic clinical improvement was achieved. In one case a marked increase of the surrounding brain edema occurred 7days after radiosurgery, who was operated on. The radiation dose was based on the volume, location and radiosensitivity of the lesion which ranged 15-40 Gy.